This invention relates to a face protector, a seal device for a face protector and a method for making such seal device and, more particularly, to a seal device for a face protector having an improved fitness to the user's face.
Various face protectors are used for securing safety for a person working in an adverse or dangerous environment. For protecting the respiratory system, for example, respiratory system protectors including a dust proof mask, a gas mask, an air supply mask, an air respirator and an oxygen respirator are used. For protecting eyes, for another example, protectors including a shading protector and eye protecting glasses for welding are used. There are also some protectors having these functions of protecting the respiratory system and eyes combined together.
The face protectors such as these respiratory system protectors and eye protecting glasses which are worn by users must be fitted closely to their face and there should be no leakage between the protectors and their face. Otherwise, the function of the face protectors would not be performed fully and an adequate level of safety would not be secured.
A respiratory system protector in the form of a half face mask covering the user's mouth and nose, for example, must be completely sealed in its peripheral portion because otherwise concentration of newly supplied air or oxygen would not be maintained at a predetermined value.
For improving seal characteristics of such half face mask, the prior art half face mask is provided with a seal member made of an elastic material such as rubber at the peripheral portion of the mask and, besides, masks of many sizes are prepared for enabling the user to choose a mask of an optimum shape and size which fits his face most closely.
Since, however, the contour and skeletal structure of the user's face differs in minute details from one person to another, the prior art half face mask which is adapted to fit the user's face by utilizing elasticity of the seal member and choosing a suitable one from masks of various sizes is still insufficient for satisfying all users of the mask in wearing the mask in an adequately fitted state.
A safety measure is taken to cope with such situation by conducting a fitting test for masks by a relevant organization or by conducting a mask wearing training for persons who want to wear the masks. Thus, fitting of face protectors is a great problem for manufacturers as well as users of the face protectors.
For coping with the situation, it is conceivable to increase the types of masks or manufacture a mask in conformity with the face of an individual user. These measures however are not practicable because they will require molds for forming masks and this will require a long period of time in completing masks and will also be very costly.
It is also conceivable to make a mold for a mask by placing a lump of plaster on a user's face and forming this plaster into a mold in conformity with his face. This method however has the problems that it takes a long time before the plaster mold hardens and that it is extremely difficult for the user to form such plaster mold by himself without assistance by other person.
An improvement in straps attached to these face protectors is also proposed in addition to the improvement in the face protector themselves but a remarkable success has not been reported yet.
It is, therefore, an object of the invention to provide a seal device for a face protector capable of fitting a face protector to the user's face closely regardless of difference in the contour or skeletal structure of the user's face from one user to another.
It is another object of the invention to provide a face protector having such seal device.
It is still another object of the invention to provide a method for forming such seal device for a face protector.